bash 如何在 makefile shell 命令中使用管道？
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how do I use pipes in a makefile shell command?
提问by dhruvbird
I have the following code snippet in a Makefile which always fails unless I remove the references to sed & grep below.
我在 Makefile 中有以下代码片段，除非我删除下面对 sed 和 grep 的引用，否则它总是失败。
TAB=$(shell printf "\t")
all: abstract.tsv
$(shell cut -d "${TAB}" -f 3 abstract.tsv | sed "s/^\s*//" | \
sed "s/\s*$//" | grep -v "^\s*$" | sort -f -S 300M | \
uniq > referenced_images.sorted.tsv)
This is the error I get:
这是我得到的错误：
/bin/bash: -c: line 0: unexpected EOF while looking for matching `"'
/bin/bash: -c: line 1: syntax error: unexpected end of file
What could be wrong?
可能有什么问题？
回答by William Pursell
One error is coming from sed. When you write:
一个错误来自sed. 当你写：
sed "s/\s*$//"
make expands the variable $/to an empty string, so sed is missing a delimiter. Try:
make 将变量扩展为$/空字符串，因此 sed 缺少分隔符。尝试：
sed "s/\s*$$//"
Using $"is causing the same problem in grep. Use grep -v "^\s*$$"instead.
使用$"是导致同样的问题grep。使用grep -v "^\s*$$"来代替。
